August 29, 2016
Recommended Topic Related To:


"Jan. 1, 2013 -- Antidepressant use during pregnancy, long debated for its safety, is linked with a higher overall risk of stillbirth and newborn death. Now, a new study shows that risk may not be warranted.

"After taking maternal char"...



Remeron Side Effects Center

Medical Editor: John P. Cunha, DO, FACOEP

Last reviewed on RxList 7/8/2016

Remeron (mirtazapine) is a tetracyclic antidepressant used to treat depression. Remeron is available in generic form (mirtazapine). Remeron has been used to treat nausea, anxiety, post traumatic stress syndrome, and used as an appetite stimulant. Common side effects of Remeron include:

  • drowsiness
  • increased appetite
  • weight gain
  • dizziness, and
  • nausea

Tell your doctor if you experience serious side effects of Remeron including agitation, hallucinations, fever, fast or uneven heart rate, loss of coordination or feeling unsteady, stiff muscles, confusion, tremors, flu symptoms, memory problems, weakness, overactive reflexes, nausea, vomiting, diarrhea, loss of coordination, sweating, feeling like you might pass out, chills, body aches, white patches or sores inside your mouth or on your lips, headache, or trouble concentrating.

Remeron is usually given as tablets 15 - 45 mg/day, administered in a single dose, preferably in the evening before sleep, with or without food. Dosages are increased, if necessary, slowly over one to two weeks. Serious side effects, such as suicide risk, behavior changes and an increase in depression have been documented. Remeron can increase the sedating effects of benzodiazepines, narcotics, tricyclics and other medications. Remeron should not be used with monoamine oxidase inhibitors (MAOI). This drug is not approved for pediatric patients. Pregnant and lactating females should consult with their physicians before starting this drug.

Our Remeron Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What is Patient Information in Detail?

Easy-to-read and understand detailed drug information and pill images for the patient or caregiver from Cerner Multum.

Remeron in Detail - Patient Information: Side Effects

Get emergency medical help if you have any of these signs of an allergic reaction: skin rash or hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Report any new or worsening symptoms to your doctor, such as: mood or behavior changes, anxiety, panic attacks, trouble sleeping, or if you feel impulsive, irritable, agitated, hostile, aggressive, restless, hyperactive (mentally or physically), more depressed, or have thoughts about suicide or hurting yourself.

Call your doctor at once if you have a serious side effect such as:

  • agitation, hallucinations, fever, fast heart rate, overactive reflexes, nausea, vomiting, diarrhea, loss of coordination;
  • very stiff (rigid) muscles, high fever, sweating, confusion, fast or uneven heartbeats, tremors;
  • feeling like you might pass out;
  • fever, chills, body aches, flu symptoms;
  • white patches or sores inside your mouth or on your lips; or
  • headache, trouble concentrating, memory problems, weakness, or feeling unsteady.

Less serious side effects include:

  • drowsiness, dizziness;
  • increased appetite; or
  • weight gain.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Read the entire detailed patient monograph for Remeron (Mirtazapine)

What is Patient Information Overview?

A concise overview of the drug for the patient or caregiver from First DataBank.

Remeron Overview - Patient Information: Side Effects

SIDE EFFECTS: See also the Warning section.

Dizziness, drowsiness, lightheadedness, increased appetite, weight gain, dry mouth, or constipation may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.

To relieve dry mouth, suck on (sugarless) hard candy or ice chips, chew (sugarless) gum, drink water or use a saliva substitute.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor right away if you have any serious side effects, including: swelling of the hands/feet, shaking (tremor), confusion, signs of infection (e.g., fever, persistent sore throat).

Get medical help right away if you have any very serious side effects, including: fast/irregular heartbeat, severe dizziness, fainting, eye pain/swelling/redness, vision changes (such as seeing rainbows around lights at night, blurred vision).

This medication may increase serotonin and rarely cause a very serious condition called serotonin syndrome/toxicity. The risk increases if you are also taking other drugs that increase serotonin, so tell your doctor or pharmacist of all the drugs you take (see Drug Interactions section). Get medical help right away if you develop some of the following symptoms: fast heartbeat, hallucinations, loss of coordination, severe dizziness, severe nausea/vomiting/diarrhea, twitching muscles, unexplained fever, unusual agitation/restlessness.

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Read the entire patient information overview for Remeron (Mirtazapine)

What is Prescribing information?

The FDA package insert formatted in easy-to-find categories for health professionals and clinicians.

Remeron FDA Prescribing Information: Side Effects
(Adverse Reactions)


Adverse Drug Reaction Overview

Adverse Events Leading to Discontinuation of Treatment

Sixteen percent of patients treated with REMERON® Tablets in U.S. short-term controlled studies discontinued treatment due to an adverse event, compared to 7% of patients treated with placebo. The adverse event that accounted for more than 5% of discontinuations with REMERON® was somnolence (10%).

Commonly Observed Adverse Events in U.S. Short-Term Controlled Clinical Trials

The most commonly observed adverse events related to the use of REMERON® Tablets (5% or greater drug-related incidence for REMERON® Tablets and at least twice that of placebo) were somnolence (54% vs. 18%), increased appetite (17% vs. 2%), weight gain (12% vs. 2%) and dizziness (7% vs. 3%).

Clinical Trial Adverse Drug Reactions

Because clinical trials are conducted under very specific conditions the adverse drug reaction rates observed in the clinical trials may not reflect the rates observed in practice and should not be compared to the rates in the clinical trials of another drug. Adverse drug reaction information from clinical trials is useful for identifying drug-related adverse events and for approximating rates.

Adverse Events Occurring at an Incidence of 1% or More Among REMERON®-Treated Patients

The table that follows enumerates adverse events that occurred at an incidence of 1% or more among REMERON®-treated patients (and greater than the incidence in placebo-treated patients) who participated in U.S. short-term placebo-controlled trials, in which patients were dosed in a range of 5 to 60 mg/day. The investigators reported adverse clinical experiences using terms of their own choice. Reported adverse events were then classified using the standard COSTART-based dictionary terminology.

The prescriber should be aware that these figures cannot be used to predict the incidence of side effects in the course of usual medical practice where patient characteristics and other factors differ from those which prevailed in the clinical trials. Similarly, the cited frequencies cannot be compared with figures obtained from other investigations involving different treatments, uses and investigators. The cited figures, however, do provide the prescribing physician with some basis for estimating the relative contribution of drug and non-drug factors to the side effect incidence rate in the population studied.

TABLE 1: Incidence of adverse clinical experiences ( ≥ 1% for REMERON®) in U.S. short-term placebo controlled studies1,2,3

Body System Adverse Event REMERON®
N = 453
N = 361
Body as a Whole
  Asthenia 34 (8%) 17 (5%)
  Flu Syndrome 22 (5%) 9 (3%)
  Back Pain 9 (2%) 3 (1%)
Digestive System
  Dry Mouth 112 (25%) 54 (15%)
  Increased Appetite 76 (17%) 7 (2%)
  Constipation 57 (13%) 24 (7%)
Metabolic and Nutritional Disorders
  Weight Gain 54 (12%) 6 (2%)
  Peripheral Edema 11 (2%) 4 (1%)
  Edema 6 (1%) 1 (0%)
Musculoskeletal System
  Myalgia 9 (2%) 3 (1%)
Nervous System
  Somnolence 243 (54%) 65 (18%)
  Dizziness 33 (7%) 12 (3%)
  Abnormal Dreams 19 (4%) 5 (1%)
  Thinking Abnormal 15 (3%) 4 (1%)
  Tremor 7 (2%) 2 (1%)
  Confusion 9 (2%) 1 (0%)
Respiratory System
  Dyspnea 5 (1%) 1 (0%)
Urogenital System
  Urinary Frequency 8 (2%) 5 (1%)
N= Number of Patients
1 % rounded off to the nearest whole integer.
2 Events which had an incidence on placebo > REMERON®: infection, pain, headache, nausea, diarrhea and insomnia.
3 Events which had an incidence of REMERON® comparable to placebo: chest pain, palpitation, tachycardia, postural hypotension, dyspepsia, flatulence, libido decreased, hypertonia, nervousness, rhinitis, pharyngitis, sweating, amblyopia, tinnitus and taste perversion.

There was evidence of adaptation to some adverse events with continued therapy (e.g., increased appetite, dizziness and somnolence).

ECG Changes

The electrocardiograms for 338 patients who received REMERON® and 261 patients who received placebo in the U.S. short-term controlled trials were analyzed, in which the QTc calculations using the method of Fridericia was employed. Prolongation in QTc ≥ 500 msec was not observed among mirtazapine-treated patients. Mean change in QTc was +1.6 msec for mirtazapine and -3.1 msec for placebo. Mirtazapine was associated with a mean increase in heart rate of 3.4 bpm, compared to 0.8 bpm for placebo. The clinical significance of these changes is unknown.

Less Common Clinical Trial Adverse Drug Reactions ( < 1%)

During worldwide controlled and uncontrolled clinical trials, REMERON® was administered to 2,796 patients. The listing of events which follows includes those events which were judged by the investigator to be adverse clinical experiences. The investigators used terminology of their own choice to describe the adverse experiences. Consequently, it is not possible to provide a meaningful estimate of the proportion of individuals experiencing adverse events without first grouping similar types of untoward events into a smaller number of standardized categories. It is important to emphasize that although the events occurred during treatment with REMERON®, they were not necessarily drug-related. Following the adverse experiences tabulations, the incidence of clinically significant laboratory values which occurred at a rate of ≥ 1% of patients is presented.

In the tabulations that follow, adverse events as reported by the investigator were classified using a standard COSTART-based dictionary terminology. Events are further categorized by body system and listed in order of decreasing frequency according to the following definitions: frequent adverse events are those occurring on one or more occasions in at least 1/100 patients, infrequent adverse events are those occurring in 1/100 to 1/1,000 patients, and rare events are those occurring in fewer than 1/1,000 patients. Only those events not already listed in Table 1 appear in this listing. Events of major clinical importance are also described in the WARNINGS AND PRECAUTIONS section.

Body as a Whole: frequent: malaise, abdominal pain, abdominal syndrome acute; infrequent: chills, fever, face edema, ulcer, photosensitivity reaction, neck rigidity, neck pain, abdomen enlarged; rare: cellulitis, substernal chest pain.

Cardiovascular System: frequent: hypertension, vasodilatation; infrequent: angina pectoris, myocardial infarction, bradycardia, ventricular extrasystoles, syncope, migraine, hypotension; rare: atrial arrhythmia, bigeminy, vascular headache, pulmonary embolus, cerebral ischemia, cardiomegaly, phlebitis, left heart failure.

Digestive System: frequent: vomiting, anorexia; infrequent: eructation, glossitis, cholecystitis, nausea and vomiting, gum hemorrhage, stomatitis, colitis, liver function tests abnormal; rare: tongue discolouration, ulcerative stomatitis, salivary gland enlargement, increased salivation, intestinal obstruction, pancreatitis, aphthous stomatitis, cirrhosis of liver, gastritis, gastroenteritis, oral moniliasis, tongue edema.

Endocrine System: rare: goiter, hypothyroidism.

Hemic and Lymphatic Systems: rare: lymphadenopathy, leukopenia, petechia, anemia, thrombocytopenia, lymphocytosis, pancytopenia.

Metabolic and Nutritional Disorders: frequent: thirst; infrequent: dehydration, weight loss, rare: gout, SGOT increased, healing abnormal, acid phosphatase increased, SGPT increased, diabetes mellitus.

Musculoskeletal System: frequent: myasthenia, arthralgia; infrequent: arthritis, tenosynovitis; rare: pathologic fracture, osteoporosis fracture, bone pain, myositis, tendon rupture, arthosis, bursitis.

Nervous System: frequent: hypoesthesia, apathy, depression, hypokinesia, vertigo, twitching, agitation, anxiety, amnesia, hyperkinesia, paresthesia; infrequent: aggression, ataxia, delirium, delusions, depersonalization, dyskinesia, extrapyramidial syndrome, libido increased, coordination abnormal, dysarthria, hallucinations, manic reaction, neurosis, dystonia, hostility, reflexes increased, emotional lability, euphoria, paranoid reaction; rare: aphasia, nystagmus, akathisia, stupor, dementia, diplopia, drug dependence, paralysis, grand mal convulsion, hypotonia, myoclonus, psychotic depression, withdrawal syndrome.

Respiratory Systems: frequent: cough increased, sinusitis; infrequent: epistaxis, bronchitis, asthma, pneumonia; rare: asphyxia, laryngitis, pneumothorax, hiccup.

Skin and Appendages: frequent: pruritus, rash; infrequent: acne, exfoliative dermatitis, dry skin, herpes simplex, alopecia; rare: urticaria, herpes zoster, skin hypertrophy, seborrhea, skin ulcer.

Special Senses: infrequent: eye pain, abnormality of accommodation, conjunctivitis, deafness, keratoconjunctivitis, lacrimation disorder, glaucoma, hyperacusis, ear pain; rare: blepharitis, partial transitory deafness, otitis media, taste loss, parosmia.

Urogenital System: frequent: urinary tract infection; infrequent: kidney calculus, cystitis, dysuria, urinary incontinence, urinary retention, vaginitis, hematuria, breast pain, amenorrhea, dysmenorrhea, leukorrhea, impotence, rare: polyuria, urethritis, metrorrhagia, menorrhagia, abnormal ejaculation, breast engorgement, breast enlargement, urinary urgency.


The following adverse events were observed commonly in clinical trials in children: significant weight gain ( ≥ 7 %) was observed in 48.8 % of the REMERON® treated subjects compared to 5.7 % in the placebo arm; urticaria (11.8 % vs. 6.8 %) and hypertriglyceridaemia (2.9 % vs. 0 %) were also commonly observed. (See also ACTION AND CLINICAL PHARMACOLOGY Special Populations and Conditions/Pediatrics).

Abnormal Hematologic And Clinical Chemistry Findings

Abnormal Laboratory Values

Elevated cholesterol, serum glucose and triglycerides were the most common blood chemistry parameters observed in U.S. studies.

The plasma samples were drawn from non-fasting patients, and these parameters are affected by diet. Patients taking REMERON® had increased appetite and weight gain, and are likely to have had increased food intake. Increased food intake may account for the increased triglyceride and cholesterol values. Moreover, LDL:HDL ratio data from a limited number of patients suggest that fat metabolism does not change with REMERON® treatment, further suggesting that the increase in triglyceride and cholesterol values reflected increased dietary intake.

Mild changes in liver function are shown by increases in liver enzymes. However, changes are temporary, mild, and are not expected to negatively influence liver function. Premature terminations due to liver enzyme abnormalities were, respectively, REMERON®, 1.7% and placebo, 1.1%.

The incidence of neutropenias in all clinical studies for REMERON® was 1.5%. Most of the observed cases of neutropenia were mild isolated and nonprogressive (see WARNINGS AND PRECAUTIONS).

Post-Market Adverse Drug Reactions

Adverse Events Observed During Post-Marketing Evaluation of REMERON®

Note: Adverse events reported during clinical trials, which were also reported during post-marketing, are not included in this section.

Adverse events reported since market introduction, which were temporally (but not necessary causally) related to mirtazapine therapy, include four cases of the ventricular arrhythmia torsades de pointes. In three of the four cases, however, concomitant drugs were implicated. All patients recovered.

Adverse events are listed under the appropriate System Organ Class

Blood and lymphatic system disorders: bone marrow depression (granulocytopenia, agranulocytopenia, aplastic anemia) (see also WARNINGS AND PRECAUTIONS, Agranulocytosis), eosinophilia.

Metabolism and nutrition disorders: hyponatremia.

Psychiatric disorders: insomnia, nightmares, psychomotor restlessness, suicidal ideation, suicidal behaviours.

Nervous system disorders: headache, oral paresthesia, serotonin syndrome, restless legs, syncope, lethargy, sedation.

Investigations: electrocardiogram QT prolonged, increased creatine kinase.

Cardiac disorders: cardiac arrest, long QT, torsade de pointes, sudden death, ventricular arrhythmia (torsade de pointes), ventricular fibrillation, ventricular tachycardia.

Vascular disorders: orthostatic hypotension

Gastrointestinal disorders: diarrhea, mouth edema, oral hypoaesthesia.

Skin and subcutaneous tissue disorders: Stevens-Johnson syndrome, dermatitis bullous, erythema multiforme, toxic epidermal necrolysis.

General disorders and administration site conditions: Generalized and local edema, fatigue.

Adverse Reactions following Discontinuation of Treatment (or Dose Reduction)

There have been reports of adverse reactions upon the discontinuation of REMERON® (particularly when abrupt), including but not limited to the following: dizziness, abnormal dreams, sensory disturbances (including paresthesia and electric shock sensations), agitation, anxiety, fatigue, confusion, headache, tremor, nausea, vomiting and sweating or other symptoms which may be of clinical significance (see WARNINGS AND PRECAUTIONS and DOSAGE AND ADMINISTRATION).

Patients should be monitored for these or any other symptoms. A gradual reduction in the dosage over several weeks, rather than abrupt cessation, is recommended whenever possible. If intolerable symptoms occur following a decrease in dose or upon discontinuation of treatment, dose titration should be managed on the basis of the patient's clinical response. These events are generally self-limiting. Symptoms associated with discontinuation have been reported for other anti-depressants with serotonergic effects (see WARNINGS AND PRECAUTIONS and DOSAGE AND ADMINISTRATION).

Read the entire FDA prescribing information for Remeron (Mirtazapine)

Remeron - User Reviews

Remeron User Reviews

Now you can gain knowledge and insight about a drug treatment with Patient Discussions.

Here is a collection of user reviews for the medication Remeron sorted by most helpful. Patient Discussions FAQs

Report Problems to the Food and Drug Administration


You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

Emotional Wellness

Get tips on therapy and treatment.